“The film’s structure, which is basically a chase in the second half, is pretty conventional by the standards of the day. Griffith uses his usual jump cuts to set up and intensify the tension leading up to what one expects to be Walthall’s rescue or change of heart. But there is no rescue – and there is no change of heart. I have to conclude that the climax was quite a shock for the audience in 1913. One has to ask oneself what Griffith was thinking when he made this decision. The writing credit goes to a William E. Wing, a relative newcomer to film writing. But Griffith could certainly have changed the ending had he wanted to. There’s something just a little diabolical about Death’s Marathon – it’s as though Griffith had wanted to finally let the audience know that he would not always let them off the hook – thus returning credibility for suspense to a medium that might have been becoming a bit too predictable by 1913.
Whatever else can be said about Death’s Marathon, there’s a kind of sadistic fun at work in it, and nowhere is this more apparent than in Walthall’s long and strange performance over the phone to his wife and partner. One cannot tell what he is saying, but he is certainly taking his time about it. He grins evilly at the gun throughout the long conversation, knowing for certain it is what he is going to do. What he seems to relish is the torture that he is putting his wife through on his way to oblivion.”Pete GoochThe World Cinema Canon